title: Morphological and physiological characterization of pyramidal neuron subtypes in rat medial prefrontal cortex.
abstract: The medial prefrontal cortex (mPFC) has been implicated in cognitive and executive processes including decision making, working memory and behavioral flexibility. Cortical processing depends on the interaction between distinct neuronal cell types in different cortical layers. To better understand cortical processing in the rat mPFC, we studied the diversity of pyramidal neurons using in vitro whole-cell patch clamp recordings and biocytin staining of neurons, followed by morphological analysis. Using unsupervised cluster analysis for the objective grouping of neurons, we identified more than 10 different pyramidal subtypes spread across the different cortical layers. Layer 2 pyramidal neurons possessed a unique morphology with wide apical dendritic field spans and a narrow basal field span. Layer 3 contained the only subtype that showed a burst of action potentials upon current injection. Layer 5 pyramidal neurons showed the largest voltage sags. Finally, pyramidal neurons in layer 6 (L6) showed a great variety in their morphology with 39% of L6 neurons possessing tall apical dendrites that extend into layer 1. Future experiments on the functional role of the mPFC should take into account the great diversity of pyramidal neurons.
authors.affiliation: Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Current address: Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Science, 1105 BA Amsterdam, The Netherlands.
authors.forename: Karlijn I
authors.initials: KI
authors.lastname: van Aerde
authors.affiliation: Forschungszentrum Jülich, Institute of Neuroscience and Medicine, INM-2, D-52425 Jülich, Germany Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Medical School, D-52074 Aachen, Germany Jülich Aachen Research Alliance, Translational Brain Medicine (JARA-Brain), D-52074 Aachen, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Feldmeyer
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D005260:Female; D008297:Male; D008564:Membrane Potentials; D017397:Prefrontal Cortex / Q000166:cytology / Q000502:physiology*; D017966:Pyramidal Cells / Q000166:cytology* / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
keywords: 3D reconstructions; classification; cluster analysis; heterogeneity; layers; patch clamp